About 160 scientists have protested in Geelong as part of nation-wide demonstrations against cuts to the CSIRO in the federal budget.

The CSIRO plans to axe about 500 jobs after more than $100 million was cut from the organisation in the May budget.

Staff at the Australian Animal Health Laboratory (AAHL) in Geelong have not been told whether they will be affected by the cuts but fear up to 20 jobs could go.

Researcher and CPSU representative Vicky Boyd, who works with diseases that pass from animals to humans at the AAHL, said the cuts across the CSIRO were devastating.

"We're learning more about these diseases so we can stop the spread," Ms Boyd said.

"The work that we do is quite vital.

"It's vital to the Australian community and unfortunately these federal cuts to our science budget are affecting us at the ground level - we're actually losing scientists at the bench level that do this vital research."

Ms Boyd said any cuts in Geelong would hit hard.

"Particularly in Australia, and in Geelong, we're losing our industry and at least I thought we were perhaps going to grow with innovation and our science, but all that is being cut as well," she said.

CSIRO protests around the country

Similar protests have been held in Geraldton, Alice Springs, Townsville, Newcastle and Griffith.

In Griffith 10 employees expressed concern that the city's laboratory would close in 2016.

Alice Springs researcher Jocelyn Davies said the Central Australian laboratories were some of the oldest and would need to be renovated soon in order to continue operating.

"The future for CSIRO in Alice Springs, when the lab is 64, may be the end of its life expectancy," Ms Davies said.

"That's pretty sad because CSIRO has been part of the big science innovation and knowledge innovation that is Alice Springs."

Ms Davies said the local laboratories, which employed 11 people, had been leading the field in making dry and barren areas more liveable.

"How people and economies can thrive in places like this, we've actually been applying that research very recently, for last two years into the Australian Government's research for development program in Africa.

"(These are) marginal environments, so how do you actually make a difference in these kind of places?"

The Acting Secretary of the CSIRO Staff Association Dr Michael Borgas said the situation was unprecedented.

"It's no exaggeration to say that CSIRO faces a jobs crisis," he said.

"We could be looking at the largest reduction in staffing at CSIRO in the organisation's history."